In theory, female orgasms serve an evolutionary purpose of increasing fertility by increasing the retention of sperm. One of the surprising pieces of information here is that in order for female orgasms to increase fertility a woman has to have one within one minute before and 45 minutes after male ejaculation. The reason that I find this surprising, is that for most couples simultaneous orgasms, or female orgasm following male orgasm, are rare (unless of course, as Rick Mercer has implied, the woman is covertly taking care of her own needs after dispensing with her partner).
A new paper, in press at Evolution and Human Behavior, examines the timing and frequency of female orgasms and finds evidence to support my priors that, on average, women have orgasms before men and that most frequently they involve some activity other than intercourse.*
The orgasm frequency found among the participants in their study is as follows:
Coital orgasm before ejaculation – 42%
Coital orgasm during ejaculation – 28%
Coital orgasm after ejaculation – 33%
Non-coital partners orgasm – 54.5%
Self masturbatory orgasm – 72%
What is fascinating about this evidence is that the authors find that if the man in the couple is very attractive and/or very masculine, the woman is significantly more likely to have an orgasm either at the same time as her partner, or just after. So the timing of orgasms for women with attractive partners coincides with the period that increases fertility supporting the argument that orgasms play an evolutionary function – women orgasm more frequently and with better timing when their partners have better genes.
This isn’t just because they are more turned on by their hot partners. Women with attractive partners do have orgasms more frequently in general, but the frequency of orgasms during sexual activities other than intercourse has nothing to do with the attractiveness her partner.
I know this isn’t really an economic issue but I couldn’t resist. Maybe orgasm timing and frequency is tied to other measures of fitness – like income and power? Now then you could have a paper the American Economic Review might publish (okay, probably not).
* Puts, David, Lisa L.M. Welling, Robert P. Burriss, and Khytam Dawood (2011). “Men’s masculinity and attractiveness predict their female partner’s reported orgasm frequency and timing”. Forthcoming.